An ore-bin, which will hold about 220 long tons, receives the ore from the aerial tramway. From this it is shovelled down two shoots into two 16 x 10 inch Blake crushers, running at 240 r p.m. and the crushed material falls on to two shaking screens of 1¼ inch steel plate perforated by 1½ inch diameter holes. They are set at a slope of 29 degrees and make 200 of 1½ inch strokes per minute. The undersize goes directly to the elevator boot and the oversize falls into two 10 x 7 inch Blake crushers running at 218 r.p.m. and thence to the elevator. The shaking screen eccentrics are on a shaft driven from a pulley on an extension of the shaft of one of the large breakers. Any stoppage of this breaker stops both screens, but otherwise the two crushing sets are independent of each other.
Shearing toggles, composed of two halves held together by six 1 inch rivets, are used on the small breakers. The strain occasioned by a hammer head getting between the jaws is sufficient to shear all these rivets and thereby save the main parts of the machine.
The elevator runs at 170 buckets p.m. of 0.2 cubic feet capacity. When dealing with clayey material (such as that found near the Woodstock fault) the buckets have to be cleaned out occasionally. The elevator delivers to 15 inch belt conveyor 52 feet long, running at 260 ft. p.m. which delivers the ore through shoots to various parts of the main hopper with a capacity of 400 long tons (1 long ton = 25 cubic feet approx.).
That section which feeds the first ten stamps is partitioned off from the rest so that tributers' ore may be kept separate from general ore until it has passed the stamps.
The floor of the hopper is inclined at 45 degrees and the sides slope similarly near the bottom, so that it is almost self-discharging.